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I i In addition, the LUFT Manual states: "The program of implementation for achieving water quality ob3ective shall include, but not be limited to: a) A description of the nature of actions which are neces- sary to achieve the objectives, including recommenda- tions for appropriate action by any entity, public or private. b) A time schedule for actions to be taken. C) A description of surveillance to be undertaken to determine compliance with ob3ectives. Because of these considerations, interactions with the regional board (RWQCB) must occur to establish groundwater cleanup levels. 5. 0 Site Conditions 5. 1 Site Geology The subsurface geology at this site is characterized by unconsol- idated medium sands, silty and clayey sands and some clays. Medium sands predominate to depths of approximately 12 to 15 feet below ground surface (BGS) _ A dense blue green clay was encoun- tered in MW-3 at approximately 15' and extended to 24 feet BGS. At BH-2 , MW-1 and MW-2 sand was encountered throughout the extent of the borings with poorly sorted medium to coarse sands encoun- tered beginning about 23 feet BGS . In BH-2 coarse sands were found all the way to it' s full depth of 40 ft. BGS. The saturat- ed zone was encountered at 12-15 feet BGS in all locations ifi micaceous medium grained sand and silty sands. Some thin interfingerings of clay were observed but showed no lateral continuity. 5 . 2 Groundwater Gradient Subsequent to completion of the wells the top of casing eleva- tions were established by surveying the wells. The survey of the wells was tied to the previously established BM #2 (J.R. Simplot Company benchmark) . Depth to water measurements provided data used to determine the site groundwater gradient characteristics. Based on these water level data, a groundwater gradient map has been prepared indicating that the localized groundwater flow is to the northeast (see Figure 4) . It should be noted that exten- sive ongoing groundwater studies on a larger scale at this location indicate a clear regional gradient with groundwater flow to the west. The gradient of the groundwater described by data from the three site wells has a magnitude (slope) of 0. 002 (eft/1000ft) . This relatively steep gradient (compared to the shallow regional gradient) to the northeast is explained by the - 8 -